Researchers Shrink Confocal Laser Microscope

Scanning confocal laser microscopes are bulky and stay in one place. But a start-up company aims to find its success by miniaturizing these devices while still providing three-dimensional optical sectioning and high contrast.
The battery-operated instrument, created by Jim Hang and Victor Lazarev at New Dimension Research, replaces alignment mechanisms and moving parts with a matrix-ad-dressable laser detector array that provides real-time imaging on one chip.
The prototype includes a laptop computer, a vertical cavity surface- emitting laser detector array from Sandia National Laboratories as the laser source, and a confocal pinhole-like detector. Images are obtained by turning on each laser and its matched detector consecutively.
"With a single laser, mechanical parts are required for scanning," said Hang, adding that imaging rates for conventional confocal laser microscopes are 15 frames per second. The new instrument images at four times that rate, enabling researchers to view such rapidly occurring events as protein-to-protein exchanges.

Compact design
The new microscope should appeal to "important, possibly niche, markets since the device will be capable of getting into small places without the need for optics," said Rob Webb of Wellman Laboratories at Massachusetts General Hospital, a co-inventor of the device and founder of confocal laser scanning microscopy. "This is a very great example of how the SBIR [Small Business Innovation Research] system works. This work isn't in the academic purview. The SBIR program enables you to take on risky things."
Konan Inc., a Japanese company that produces instruments for ophthalmology, is interested in licensing the new technology. "The problem with existing confocal instruments is the tremendous cost," said Susan Oak, a representative for Konan. "Hang's device would be well below the $50,000 to $100,000 price tag for a confocal instrument for ophthalmological applications."
The instrument also uses infrared light, which reduces problems associated with stray light. Another factor for manufacturers is the design's reliance on a bi-lens, eliminating sophisticated alignment mechanisms.
Although a commercial device is still two years away, applications may include verification of retinal signature, drug development, cancer detection, environmental monitoring and process control.